Stop for power-presses



(No Model.)

W. B. WALLACE;

STOP FOR POWER PRESSES.

2 Sheets-Sheet 1..

Fi3 l Patented June 29, 1897..

PI -:1 5 Z m, 3Mcwtoz' L amAgwlllax/ei (No Model 2 Sheets-Sheet 2. W B WALLACE STOP FOR POWER PRESSES.

No. 585,322. Patented June 29,1897.

1 EMS cu, wmou'mo wnsumo IJNTTED STATES WVILLIAM B. WALLACE, OF NORWICH, CONNECTICUT.

STOP FOR POWER-PRESSES.

SPECIFICATION forming part of Letters PatentNo. 585,322, dated June 29, 1897. Application filed October 21, 1895. Serial No. 566,444. (No model.)

To all whom it may concern:

Be it known that I, WILLIAM B. WALLACE, a citizen of the United States, residing at Norwich, in the county of New London and State of Connecticut, have invented certain new and useful Improvements in Stops for Power- Presses, which improvements are fully set forth and described in the following specifi-.

cation, reference being had to the accompanying sheets of drawings.

This invention consists of an attachment for that class of presses or punches in which the stock to be punched is introduced to the machine in the web or strip and is fed along intermittently between the successive movements of said punch; and my object is to provide a simple, inexpensive, and effective device which shall serve as a combined stop and gage to limit the forward travel of said strip. By thus controlling positively the feed movement of the strip the machine may be safely operated at a much more rapid rate than when the strip is moved and adjusted wholly by hand, as now most commonly practiced. A marked saving of stock is also effected by the use of my improved device.

My said improvement is of such form that it may be readily attached to presses as now constructed.

To explain said invention most clearly, I have annexed hereto two sheets of drawings in which- Figures 1 and 2 are respectively side and front elevations of portions of a power-press having my stop mechanism properly attached thereto. Fig. 3 is a plan view of a strip of material partly punched, showing the relative positions of the punch and my new stop. Fig.

4 illustrates a modified means, hereinafter explained in detail, for supporting the principal shaft of my device. Figs. 5, 6, and 7 are respectively plan, rear side, and end views of my device detached from the press; and Fig. 8 illustrates the threaded portion of said principal shaft.

Referring to the drawings, the letter a indicates ahanger of bracket form, that is here shown as screwed to the head A of the press immediately at the rearof the vertically-reciprocating carriage B. 1) denotes a punch secured to and movable with said carriage,

and 0 denotes a die secured to the bed of the press.

(1 indicates a rock-shaft which in Figs. 1, 2, 5, o, and 7 is shown as journaled in hanger a. This shaft could, however, be hung on centers between pendent brackets or plates d, as shown in Fig. 4, but I prefer to use the hanger a for the reason thatit affords a more convenient means for endwise adjustment of the shaft, as I shall explain. It will be noticed that said shaft d is supported only at one end, thus leaving the exposed portionfree to receive and support other operative elements of my device. That portion of said shaft that is journaled in hanger Ct is formed with right and left hand screw-threads d (i each of which has mounted thereon a nut d and check-nut d and it will be understood that by properly regulating said nuts the shaft may be adjusted longitudinally in the hanger. Secured to said shaft by set-screw e is an arm 6, extending toward the punch h and having journaled in its free end a short rock-shaft 6 One end of shaft e is formed with a head e whose circumferential edge is cut away or notched, as at e 6 and within one of said notches e is located a pin f, that is driven into the arm 6' and serves as a stop to limit the rotary movement of shaft e 6 indicates a collar secured on said shaft 6 to prevent endwise displacement of said shaft. Secured to and coiled around the projecting end of shaft 6 is a spring g, whose other end is secured to a stud g, driven or screwed into the arm 6, said spring acting with a constant tendency to rock the shaft in the direction opposite to that indicated by the arrow in Fig. 7.

7?. denotes a spring, one of whose ends is fastened to set-screw e and its other end to a stud or screw ct in the upper rear portion of the hanger a. This spring 77. acts by compression to draw the set-screw a quickly upward, and thus depress the front end of arm e and its shafte It would be quite practicable when punching longblanks to dispense with spring h and rely upon gravity to rock the shaft at back to its normal position, but for nearly all classes of work I prefer to use the spring. Secured to rock-shaft d, near its free end, is a collar formed with an arm 10 that extends toward the front of the press and is drilled or slotted to receive a rod 0%, whose outer end is bent downward, as at m, and preferably in a lateral direction, as at m so that the end of said rod may be brought close to the punch by suitably adjusting the collar on shaftd. Rod m is secured in place in arm 70 by one or more set-screws a, and by easing back said screws the rod may be adjusted outward or inward in its seat to vary the position of the free end of the rod.

Referring 110w particularly to Figs. 1 and 2, it will be seen that the carriage B has secured to it a bar 0, whose lower end is formed as a hook 0, that is so located that when the carriage and punch pass downward the hook engages and rides upon the circumferential edge of the head (a of shaft 6 and finally snaps into the notch 6 When carriage B passes upward to draw the punch from the strip of metal that is being operated upon, (indicated by letter 0,) the hook 0 lifts the arm 0 against the resisting force of spring 72., thereby rocking shaft at and lifting the rod 972, whose end on has, during the punching operation, rested in one of the perforations in strip 0, preferably the one last punched. By reference to Fig. 3 said strip will be seen with several holes punched therein, the punch 19 and the end m of rod m being also shown in their respective places. Strip 0 is illustrated in said Fig. 3 as if traveling from right to left hand.

When the punch passes upward and is drawn out of the strip 0, the end of rod mis also raised out of the hole last punched by the rocking of shaft (Z, as above explained. As said punch and rod leave the strip 0 the strip is moved forward by the attendant, (in the direction of the arrow,) and as the strip starts forward shaft cl and rod mare released in a manner which I will proceed to explain, and spring hinstantly acts to return said shaft and rod to their normal positions, as in Figs. 1, 2, and 7.

I have already explained that the upward movement of carriage B causes hook 0' to lift the notched head 6 and the connected arm 6. So soon as the end m is lifted clear of strip 0 the upward movement of arm 6' is stopped by means of a screw 19, that is tapped into the upper side of arm 6 and is secured in place by a check-nut p. The upper end of said screw abuts the head of the press at the proper instant and stops the further upward movement of the arm e. Continued upward movement of the carriage and hook then results in rocking the head 6 and shaft 6 against the force of spring g in the direction of the arrow of Fig. 7 until the hook releases itself from said head, when the shaft 6 is rotated back to its normal position by spring g, and the arm 6' and shaft d are also returned to their initial positions, as above explained, by spring h.

It should be kept in mind that the end m drops before the carriage B and punch reach their highest positions and just as the strip 0 is being started forward by the attendant.

The end m thus drops either upon the uncut portion between the two holes last out or into the last hole, and thus acts as a pawl or stop that drags along until the end wall of said last hole is reached, when it serves to stop the forward movement of the strip 0. It also serves as a gage to determine exactly how much stock shall be left between the holes.

In practice the attendant has only to start the strip forward as the punch leaves it, and before said strip will have moved any considerable distance the stop-rod m will descend and check the further movement of the strip. Thus it becomes unnecessary for the attendant to pay any attention to the adjustment of the strip and he is consequently able to run the press at a much higher rate of speed than if it were necessary for him to calculate and adjust by hand the forward movement of the strip at each punching.

All of the operative partsof my device are adjustable. The shaft cl may be adjusted endwise by means of the nuts d 01 as explained. The arms 6 and 7C may be adjusted on said shaft. The rod m may be adjusted in the arm 70 and the upward travel of arm 6' may be governed by adjusting the screw 19 so that its upper end may abut the rigid head of the press earlier or later, as may be desired.

The shank of hook o is secured in carriage B by means of a set-screw 0 that allows said hook to be adjusted upward or downward. It is thus made both possible and easy to ad just the various operative elements of my device relatively to the punch to meet the varying requirements.

Having thus described my invention, I claim-- 1. In combination a fixed die and coacting punch, a rockshaft parallel with the move ment of the material to be punched, means for adjusting said shaft longitudinally in its bearings, a stop-rod secured to said shaft, means for rocking said shaft to lift the free end of said stop-rod and mechanism for forcing said free end into engagement with the material to be punched.

2. In a device of the character described, a spring-pressed rock-shaft, a stop-rod secured thereto, an arm connected to the rock-shaft, a spring-pressed shaft journaled in the end of said arm,- means for checking the movement of the rock-shaft consisting of a stud adjustably secured to the arm and means on the tool-carriage for engaging the springpressed shaft, as and for the purpose described.

3. In a device of the character described, a crank-hanger, a spring-pressed rock-shaft adjustably journaled therein, an arm on the shaft, a spring-pressed shaft journaled in the arm, a head formed on the spring-pressed shaft having notches formed therein, a pin on the arm engaging the walls of one of the notches, an adjustable stud secured to the IIO arm, a hook carried by the tool-carriage for engaging the other of said notches, and an adjustable stop-rod secured on the rock-shaft, as and for the purpose described.

4. In a machine of the character described,

a rock-shaft parallel with the movement of the material being Worked upon, means for adjusting said shaftlongitudinally in its bearings, a stop-rod 0n the shaft, means for operating' the shaft and means for timing the IQ movements of the shaft relative to the movement-s 0f the tool carried by the machine, substantially as described.

WILLIAM B. WALLACE.

Witnesses:

ALONZO M. LUTHER, FRANK I-I. ALLEN. 

